Here you will find style guides for APA, Chicago, MLA, and Scientific Style citations as well as a citation builder to help you cite your resources. In addition to this site, the Howe Library has manuals for all the major citation styles in the Reference Collection.
On this website you will also find information on EndNote, Mendeley, and Zotero, information management tools to organize your citations and help to build a complete resource list.
In the field of geography, the Annals of the Association of American Geographers (AAG), has their own style guidelines, based mostly on the Chicago Manual of Style. Here is a link to their style sheet:
Workshops on EndNote, Mendeley, and Zotero